浅析渣油催化裂化装置腐蚀与防护

目的研究渣油催化裂化装置在生产运行中存在的问题,解决该装置因腐蚀损害而造成停工停产的问题。方法对该装置典型的易腐蚀部位进行分析研究,主要包括对再生器卸剂线阀门冲蚀、膨胀节露点腐蚀、螺栓断裂的形貌分析及换热器管束端口腐蚀的具体分析,针对不同部位不同的腐蚀机理及采取的相关有效措施。结果基于上述典型案例的研究,提出该催化裂化装置日常防腐的4个措施,主要措施为强化腐蚀监测、强化施工质量监督、强化助剂管理及生产操作平稳运行。采用三指式电化学和电感腐蚀监测方式,对催化裂化装置的分馏塔顶油气系统、分馏塔顶循环系统、富气冷却系统、吸收稳定系统等易腐蚀部位进行重点监测,做到月汇总分析,根据腐蚀率进行重点关注,做好防腐和腐蚀率的对应措施。结论找准造成腐蚀的根本原因,针对腐蚀情况制定相应的应对措施,降低腐蚀速率,减低设备损坏,从而保证装置安稳长时间的运行。

Catalytic Cracking Unit Corrosion and Protection

The work aims to study the problems existing in the residue catalytic cracking unit and solve the problem of shutdown of the device due to corrosion damage. Through the analysis and research on the typical corrosion-prone parts of the device, the morphology of the valve erosion of the regenerator discharge line, the dew point corrosion of the expansion joint, the bolt fracture and the corrosion of the heat exchanger tube bundle port were analyzed in detail. According to different corrosion mechanisms, relevant effective measures were taken. Based on study on the above-mentioned typical cases, four daily anti-corrosion measures for the catalytic cracking unit were proposed. The main measures were enhanced corrosion monitoring, enhanced construction quality supervision, enhanced management of additives, and smooth operation of production operations. The three-finger electrochemical and inductive corrosion monitoring methods were used to monitor the easy-corrosive parts such as the top oil and gas system of the fractionation tower, the top circulation system of the fractionation tower, the rich gas cooling system, and the absorption stabilization system of the catalytic cracking unit, so as to achieve monthly summary analysis. Corresponding importance was attached to according to the corrosion rate, and corresponding anti-corrosion measures were taken. Identifying the root cause of corrosion and formulating corresponding countermeasures for corrosion can reduce corrosion rate, reduce equipment damage and thus ensure stable and long-term operation of the device.